my macbook is having trouble updating

Hello there, anselmo2020!

Thanks for reaching out to the Apple Support Communities! It sounds like you are having an issue with completing the installation of an update. I know how important it is to be sure your computer updates properly. What you might want to try is checking out this article with steps to Try safe mode if your Mac doesn‘t finish starting up. Even though the title mentions not starting up properly, what Safe mode does is allows your computer to restart:

• Verifies your startup disk, and attempts to repair directory issues if needed
• Loads only required kernel extensions
• Prevents Startup Items and Login Items from opening automatically
• Disables user-installed fonts
• Deletes font caches, Kernel cache and other system cache files

Once the computer is in Safe mode. Go ahead and try to install and update the computer.

Cheers!